Embodiments of the inventive concept relate generally to semiconductor devices. More particularly, embodiments of the inventive concept relate to semiconductor devices comprising electrical contacts that connect upper and lower conductive portions to each other, and methods of forming the contacts.
Semiconductor devices continue to achieve increasing levels of integration. Accordingly, critical dimensions of the devices must be decreased, and features such as vias and electrical contacts must be formed with smaller and smaller dimensions. As vias and electrical contacts are formed with smaller dimensions, they tend to exhibit smaller contact resistances, which can lead to deterioration of performance.
As an example, vias and contacts are commonly used to connect metal wires formed in different layers of a semiconductor device. The resistances of the vias or contacts are typically larger than the resistances of the metal wires, so the vias or contacts create parasitic resistances that can deteriorate overall circuit characteristics. Moreover, having a small number of contacts or vias cause an increase in parasitic resistances and a reduction in yield.